The invention relates to a motor vehicle floor comprising two rails arranged symmetrically with respect to the longitudinal axis of the vehicle.
In known constructions, each rail consists of two U-section plates superposed to form a hollow body, one of the U-section plates being beneath the floor and the other plate being above the floor and the edges of the lateral flanges of each of the U-section plates being welded to the plate of the floor, each rail comprising a bent region.
This bent region is usually situated at the front of the rail in the upwardly curved intermediate region between the floor and the bulkhead of the vehicle.
This region experiences high stresses particularly in a front impact of the vehicle.
To enable the rails to withstand the stresses, one known solution is to use a relatively large plate thickness for the two U-section plates.
This solution however, has the disadvantage of increasing the mass and cost of the rails and therefore of the vehicle.